NEW YORK -- If you think the Federal Reserve's plan to start dialing down its bond purchases later this year if the economy continues to improve is just bad for stocks, think again. The U.S. Treasury bond market, which has been a haven for investors since the 2008 financial crisis, is also taking a beating.

The yield on the 10-year Treasury note, which moves in the opposite direction of plunging prices, jumped sharply Wednesday after Fed Chairman Ben Bernanke told reporters at a press conference that the central bank would start cutting back on its monthly purchases of mortgage-backed bonds and Treasuries if the economy continues to strengthen in the months ahead as it expects.

While the Fed's stimulus program, known as quantitative easing, or QE, gets most of the credit for juicing the stock market since the market low in March 2009, it has also been a boon for bond investors, who have benefited from the Fed's buying of Treasuries and resulting higher prices.

The run-up in bond yields is due both to signs of an improving economy and the fact that the Fed, the biggest buyer of Treasuries, may be buying less later in the year.

"The 10-year Treasury bond is on the defensive," says Scott Anderson, chief economist at Bank of the West.